Enzyme embedded microfluidic paper-based analytic device (μPAD): a comprehensive review

Low-cost paper-based analytical devices are the latest generation of portable lab-on-chip designs that offers an innovative platform for the on/off-site analysis (biosensing) of target analytes, especially in rural and remote areas. Recently, microfluidic paper-based analytical devices (mu PADs) have attained significant recognition owing to their exciting fundamental features such as: ease of fabrication, rapid operation, and precise interpretations. The incorporation of enzymes with paper-based analytical devices significantly improves analytical performance while exhibiting excellent chemical and storage stability. In addition to that, these devices are highly compact, portable, easy-to-use, and do not require any additional sophisticated equipment for the detection and quantification of target analytes. This review provides a holistic insight into design, fabrication, and enzyme immobilization strategies for the development of enzyme-mu PADs, which enables them to be widely implemented for in-field analysis. It also highlights the recent application of enzyme-mu PADs in the area of: biomedical, food safety, and environmental monitoring while exploring the mechanisms of detection involved. Further, in order to improve the accuracy of analysis, researchers have designed a smartphone-based scanning tool for multi-variant point-of-care devices, which is summarized in the latter part of the review. Finally, the future perspectives and outlook of major challenges associated with enzyme-mu PADs are discussed with their possible solutions. The development of enzyme integrated mu PADs will open a new avenue as an exceptional analytical tool to explore various applications.

Automated summary

Low-cost paper-based analytical devices are a generation of portable lab-on-chip designs that provide an innovative platform for on/off-site analysis of target analytes, especially in rural and remote areas. These devices offer exciting fundamental features such as ease of fabrication, rapid operation, and precise interpretations, while incorporating enzymes to improve analytical performance. Additionally, they are compact, portable, easy-to-use, and do not require additional sophisticated equipment.